Subnet by example

- [Narrator] Let's take a look at an example…using those blocks sizes we just discussed.…If I have a class C here, 192.168.10 is my…class C network address, I'm going to…start subnetting in the fourth octet.…My first subnet is 128, really my binary which…is important but I only have one bit on at an eight.…And the fact is that, that value is 128.…255.255.255.128.…So I take 256 minus 128, it gives me a block size of 128.…

I count in increments of that block size starting at zero.…Remember where the IP subnet zero.…Zero and zero plus 128 is 128.…128 plus 128, so I just keep counting in…that increment, it actually equals 256 which I…can't use that subnet obviously.…So this is my subnet, my first one is zero.…My next subnet is 128.…And if we look, I have one subnet bit,…and two to one equals two subnets.…I have seven host bits left, so two to the…seventh is 128 minus two because for the…network and broadcast address which I can't…use gives me 126 host, two subnets, 126 host.…

Now, how do I get my broadcast address…and why is that important?…